{"nrhp_refnum":"85002801","name":"Zero Gravity Research Facility (B-2)","other_names":[],"category":"structure","location":{"address":"Lewis Research Center","address_restricted":false,"city":"Cleveland","county":"Cuyahoga County","state":"OH","lat":41.41220851700007,"lon":-81.86396082299996,"geom_source":"nps_gis"},"listed_date":"1985-10-03","is_nhl":true,"nhl_designated_date":"1985-10-03","areas_of_significance":["Other","Engineering","Science"],"significance_levels":["national"],"summary":{"what_it_is":"A vertical drop-tower research facility at NASA's Lewis Research Center in Cleveland, Ohio, consisting of a 28-foot-diameter concrete-lined shaft extending 510 feet below ground with a steel vacuum chamber inside and a ground-level service building.","why_significant":"It is described as the only facility in NASA's inventory able to study the behavior of liquids in low gravity. Its research on liquid sloshing was essential to designing high-energy upper stages such as Centaur and Saturn, which carried Americans to the moon and sent probes like Viking, Voyager and Mariner to the planets.","narrative":"Beneath the grounds of NASA's Lewis Research Center in Cleveland lies a 510-foot shaft built to create weightlessness. A 28-foot-diameter concrete-lined shaft holds a 20-foot-diameter steel vacuum chamber, 470 feet high, which is pumped down before each test. Experiment vehicles fall freely for about 5.15 seconds, or are launched upward by a pneumatic accelerator for roughly 10 seconds of free fall, then are caught in a container of polystyrene pellets. A ground-level building houses a shop, control room and clean room. Researchers used the facility for the Mercury, Gemini and Apollo programs and for Centaur rocket work, studying liquids, gases and combustion under reduced gravity. It is considered significant as NASA's only facility able to study how liquids behave in low gravity. That knowledge, especially about liquid sloshing, was essential to developing Centaur and Saturn upper stages. The facility remained in service for space shuttle experiments.","period_of_significance":"1966-Present","architect_builder":"NASA","architectural_style":null,"criteria":[],"status_note":"Listed in excellent condition, unaltered, on its original site, and in active service supporting space shuttle experiments.","vacant_flag":false,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:53:09.511128-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_OH/85002801_NHL.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/85002801/f66ed5b208-800.webp","url_1600":"https://nationalhistoricalregister.com/media/85002801/f66ed5b208-1600.webp","licence":"Public domain","author":"NASA/GRC/Paul Riedel, Al Lukas","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Zero_Gravity_Facility_-_GPN-2000-001454.jpg\" rel=\"noopener\">NASA/GRC/Paul Riedel, Al Lukas</a>, Public domain, via Wikimedia Commons","source_page":"https://commons.wikimedia.org/wiki/File:Zero_Gravity_Facility_-_GPN-2000-001454.jpg"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/71986463","wikipedia":"https://en.wikipedia.org/wiki/Zero_Gravity_Research_Facility","wikidata":"https://www.wikidata.org/wiki/Q8069520"},"indexable":true,"url":"https://nationalhistoricalregister.com/ohio/cuyahoga-county/zero-gravity-research-facility-b-2-85002801/"}